Inject into anonymous inner class (GIN)

Question

I have something like this:

request.findAllProjects().fire(new ExtReceiver<List<ProjectProxy>>() {

    @Override
    public void onSuccess(List<ProjectProxy> response) {
        view.setProjects(response);                     
    }
});

It is anonymous inner class of the abstract class ExtReceiver. The ExtReceiver is for handling the errors with an errorHandler which i want to provide.

public abstract class ExtReceiver<T> extends Receiver<T> {


    private ErrorHandler errorHandler;


    public ExtReceiver() {
    }

    @Inject
    public void setErrorHandler(ErrorHandler errorHandler)
    {
        this.errorHandler = errorHandler;
    }

    @Override
    public abstract void onSuccess(T response);

    @Override
    public void onFailure(ServerFailure error) {
        errorHandler.exception(error);
    }

    @Override
    public void onViolation(Set<Violation> errors) {
        ValidationUtils.processViolation(errors);
    }

}

I understand why this can't work, because i use the new Operator. But how could i do something like this. I want to have that anonymous class and not put it in an own file or something. How could I inject that errorHandler? Thought about staticInjections, but it looked like this does not work too (Maybe because of the inheritance i create with doing an anonymous class)

In the opposite to normal Guice i don't know an injector.getInstance() call.

For information: That is a requestFactory call

score 1 · Accepted Answer · answered Mar 28 '11 at 11:54

Why don't you put the errorHandler parameter into the constructor of your abstract class instead creating a separate setErrorHandler setter, something like this:

public abstract class ExtReceiver<T> extends Receiver<T> {

    private ErrorHandler errorHandler;

    @Inject
    public ExtReceiver(ErrorHandler errorHandler) {
         this.errorHandler = errorHandler;
    }

}

Declare the bindings:

public class MyClientModule extends AbstractGinModule {
  protected void configure() {
    bind(ErrorHandler.class).in(Singleton.class);
  }
}

Declare a Ginjector for your ErrorHandler class annotating it with the Module:

@GinModules(MyClientModule.class)
public interface MyErrorHandlerInjector extends Ginjector {
  ErrorHandler getErrorHandler();
}

and then use it like this:

MyErrorHandlerGinjector injector = GWT.create(MyErrorHandlerGinjector.class);
ErrorHandler errorHandler = injector.getErrorHandler();
request.findAllProjects().fire(new ExtReceiver<List<ProjectProxy>>(errorHandler) {      

        @Override
        public void onSuccess(List<ProjectProxy> response) {
            view.setProjects(response);

        }           
    });

I think this should work.

I ended up extended my existing Ginjector. I had only a getApp()-call which was the root. Now i have a second getErrorHandler() call. But i think this is the only solutions. Difference to your proposed solutions is that a create the injector in the staticconstruction of the ExtReceiver and not in the calling class. So i don't have to manually inject the errorHandler like you did. — ludwigm, Mar 30 '11 at 13:24

Inject into anonymous inner class (GIN)

1 Answers1